Electronic Devices with Alert Geofencing

Abstract

A communications system may include a user equipment (UE) device, a cellular network, a core network, and an emergency alert originator that broadcasts an emergency alert. The core network transmits a message to the UE that identifies a first region associated with the alert. The cellular network transmits a message to the UE that identifies a second region associated with the alert. The UE generates an expanded region as a hull around the first region and monitors its location relative to the hull. The UE displays a message body of the alert if/when the UE is within the hull and the first region is sufficiently similar to the second region. This may allow the UE to inform a user of the alert as rapidly as possible, regardless of how the cellular network and/or the core network interpret the emergency alert broadcast by the emergency alert originator.

What is claimed is: 
     
         1 . A method of operating an electronic device, the method comprising:
 receiving, using a receiver, a message from a core network, the message identifying a first geographic region associated with an emergency alert broadcast by an emergency alert originator; and   displaying, using a display, a message body of the emergency alert when the electronic device is located in a second geographic region, the second geographic region being larger than the first geographic region and including the first geographic region.   
     
     
         2 . The method of  claim 1 , wherein the message identifies the first geographic region by a set of vertices. 
     
     
         3 . The method of  claim 2 , wherein the second geographic region comprises a hull that encloses a set of polygons, each polygon in the set of polygons surrounding a respective vertex in the set of vertices. 
     
     
         4 . The method of  claim 3 , wherein each polygon in the set of polygons has an augmented radius. 
     
     
         5 . The method of  claim 4 , wherein the augmented radius is based on an expiration time of the emergency alert. 
     
     
         6 . The method of  claim 4 , wherein the augmented radius is based on a severity level of the emergency alert. 
     
     
         7 . The method of  claim 4 , wherein the augmented radius is based on an area of the first geographic region. 
     
     
         8 . The method of  claim 4 , wherein the augmented radius is based on a speed of the electronic device. 
     
     
         9 . The method of  claim 4 , further comprising:
 generating, using one or more processors, the augmented radius based on a Scaled Sigmoid Transition; and   adjusting, using the one or more processors, the augmented radius over time by adjusting one or more constants of the Scaled Sigmoid Transition.   
     
     
         10 . The method of  claim 1 , further comprising:
 discarding, using one or more processors, the message when the electronic device is located outside the second region.   
     
     
         11 . The method of  claim 1 , wherein the message comprises a hypertext transfer protocol (HTTP) message. 
     
     
         12 . The method of  claim 10 , further comprising:
 receiving, using one or more antennas, an additional message from a cellular network different from the core network, wherein the additional message identifies a third geographic region associated with the emergency alert and displaying the message body includes displaying the message body after receipt of the additional message.   
     
     
         13 . The method of  claim 11 , wherein displaying the message body further includes displaying the message body when a similarity score between the first geographic region and the third geographic region exceeds a threshold value, the method further comprising:
 discarding, using one or more processors, the message when the similarity score is less than the threshold value.   
     
     
         14 . A method of operating an electronic device, the method comprising:
 receiving, using a receiver, a first message from a core network, the first message identifying a first geographic region associated with an emergency alert broadcast by an emergency alert originator;   receiving, using one or more antennas, a second message from a cellular network different from the core network, the second message identifying a second geographic region associated with the emergency alert; and   displaying, using a display, a message body of the emergency alert when the first geographic region and the second geographic region exhibit more than a threshold level of similarity.   
     
     
         15 . The method of  claim 14 , wherein the first message identifies the first geographic region by a first set of vertices, the second message identifies the second geographic region by a second set of vertices, and displaying the message body comprises displaying the message body when each vertex in the second set of vertices is less than a threshold distance from at least one vertex in the first set of vertices. 
     
     
         16 . The method of  claim 14 , wherein the first geographic region has a first area, the second geographic region has a second area, and displaying the message body comprises displaying the message body when an area of overlap between the first geographic region and the second geographic region, divided by a larger of the first area or the second area, exceeds a threshold value. 
     
     
         17 . The method of  claim 14 , wherein the first message comprises a hypertext transfer protocol (HTTP) message. 
     
     
         18 . An electronic device comprising:
 a receiver configured to receive, from a core network, a first message identifying a first geographic area associated with an emergency alert broadcast by an emergency alert originator;   one or more antennas configured to receive, from a cellular network different from the core network, a second message identifying a second geographic area associated with the emergency alert; and   a display configured to display, based on the geographic area, a location of the electronic device, and a velocity of the electronic device, a message body of the emergency alert after receipt of the second message by the one or more antennas.   
     
     
         19 . The electronic device of  claim 18 , further comprising:
 one or more processors configured to generate, prior to receipt of the second message by the one or more antennas, an expanded geographic area based on the first geographic area and the velocity of the electronic device, the display being configured to display the message body when the electronic device is located in the expanded geographic area.   
     
     
         20 . The electronic device of  claim 19 , the one or more processors being further configured to generate the expanded geographic area based on a size of the first geographic area, an expiration time of the emergency alert as identified by the first message, and a severity level of the emergency alert as identified by the first message.